Therapeutic strategies that act on the peripheral nervous system in primary headache disorders.

Introduction: Acute and preventive treatment of primary headache disorders is not completely resolved with regard to efficacy, safety, and tolerability. Hence, peripheral and central neuromodulation can provide therapeutic alternatives in drug-resistant cases. Peripheral targets of neuromodulation include invasive and non-invasive neurostimulation and electrical and chemical nerve and ganglion blockades. Areas covered: A PubMed search of papers published from January 2012 to October 2018 was conducted. The goal of this review was to analyze the efficacy and safety of invasive (implantable) peripheral neurostimulation methods (the occipital nerve, the cervical branch of vagal nerve, the sphenopalatine ganglion) and non-invasive (transcutaneous) peripheral neurostimulation methods (the occipital nerve, the supraorbital nerve, and the cervical and auricular branches of the vagal nerve), based on the results of published clinical trials and case series. Acting also on the peripheral nervous system, peripheral nerve (i.e. greater occipital nerve) and ganglion (i.e. sphenopalatine ganglion) blockades, botulinum neurotoxin type A-hemagglutinin complex therapies, and calcitonin gene-related peptide-related monoclonal antibody treatments in this patient population are also discussed. Expert opinion: This review summarizes the latest results on the therapeutic strategies acting on the periphery in primary headache disorders. These therapeutic options are minimally invasive or non-invasive, efficacious, safe, and well tolerated.